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311.
利用2021—2022年Sentinel-2卫星搭载的多光谱成像仪(MSI)遥感数据,通过SNAP遥感软件提供的植被生物物理参数处理模块(Biophysical Processor),反演了苏州消夏湾生态安全缓冲区的5种植被生物物理参数,包括植被吸收光合有效辐射比例(FAPAR)、植被覆盖度(FVC)、叶面积指数(LAI)、冠层叶绿素含量(CCC)和冠层含水量(CWC),开展植被生态环境监测评估研究。结果表明,该生态安全缓冲区2021年建成并投入运行后,植被覆盖度和生物量有所增加,区域植被冠层结构有所改善,植被生物物理参数从一定的角度反映了消夏湾生态安全缓冲区发挥了生态涵养成效。该研究方法能在大尺度上快捷、高效地反演植被生物物理参数,可为通过植被遥感动态监测评估生态安全缓冲区的生态功能提供有益的借鉴。  相似文献   
312.
Much quantitative research examining the determinants of the ecological footprint has been conducted cross-nationally, where data on cross-boundary flows have been readily available. While local-level studies of the footprint do exist for specific localities, most quantitative research at this scale has examined direct environmental impacts attributed to the internal activities of the locality, for instance, carbon emissions. Our analysis builds on this previous work by exploiting a local-level carbon footprint dataset with coverage for 28,321 zip codes across the United States. Following prior research, we focus on the effect of local affluence, measured in terms of median household income. In spatial regression models, we regress the per capita carbon footprint on local affluence, controlling for a variety of other factors. Consistent with previous work, we find that affluence is positively correlated the carbon footprint and there is no evidence of an environmental Kuznets curve. In the conclusion, we review the results of the study and discuss their implications for policy, specifically in terms of cross-boundary environmental problems.  相似文献   
313.
根据国家相关的生态考核指标,结合南部山区生态功能保护区实际情况,建立了该区域的评价指标体系,选取多层次权重分析决策法(AHP法),对区域的生态环境质量现状及可持续发展情况做出了定量评价。  相似文献   
314.
王晶 《环境保护科学》2017,43(1):111-113
目前,生态文明视角下县域经济产业结构调整面临着工业化快速发展和生态环境日益恶化的局面,面对新的挑战,一方面必须大力发展县域绿色经济、建立县域生态消费保障机制;另一方面要转变传统产业发展模式,通过以产业结构重组实现产业结构生态化,推进生态产业发展,从而创造出一种由生态产业支撑的循环经济发展模式。  相似文献   
315.
生态城市建设理论与实践的再思考   总被引:5,自引:0,他引:5  
当前,建设生态城市是中国许多城市发展的目标取向。与国外生态城市建设相比较,我国的生态城市规划和建设尚处于初始阶段,有关生态城市的理论、规划思路、设计方法和管理机制尚在探索之中,需要多学科专家的积极参与,并力求理论和实践的新突破。为此,本刊编辑部组织了“生态城市建设”专家论坛,现将7位专家分析入理、颇有见地的精彩观点整理发表如下,以飨读者。  相似文献   
316.
松花江流域渔业生态环境汞污染现状评价   总被引:2,自引:0,他引:2  
2007~2009年对松花江干流、嫩江下游江段、第二松花江干流水质、底质和鱼类汞含量状况进行了调查研究,并参照渔业水质标准、无公害水产品产地环境要求、无公害水产品安全要求和松花江流域汞的背景值对流域生态环境汞污染进行评价.结果表明:江水中总汞含量0.000010~0.000172 mg/L,符合渔业水质标准要求;第二松...  相似文献   
317.
浙江省生态功能区划研究   总被引:5,自引:2,他引:5  
在浙江省生态环境现状调查的基础上,运用GIS等先进技术,采用定性与定量相结合的方法,对浙江省生态环境现状、生态环境敏感性和生态服务功能重要性进行评价,形成浙江省生态功能区划方案,将浙江省划分为6个生态区、15个生态亚区、47个生态功能区,并确定了具有重要生态系统服务功能的5个重要生态功能区域.区划成果为浙江生态省建设规划的实施、资源的合理利用和工农业生产合理布局提供了科学依据.  相似文献   
318.
The contribution of certain contaminants to reproductive failure in many avian species has been an ongoing concern. Appropriate quantitative techniques have focused either on the individual organisms by providing explicit bioaccumulation dynamics or on whole ecosystems by looking at the fate of the contaminant but fail to make the necessary link via population dynamics of interacting individuals. We used the individual-oriented approach in an effort to quantify effects of chronic contaminant exposure on individual birds. This was made possible by the use of an object-oriented model, where individual birds are interacting objects, and their actions are implemented by passing to them appropriate messages. Using this modeling approach a breeding colony of Great Blue Herons (Ardea herodias) is simulated as an assemblage of interacting individuals whose daily actions (foraging, growth, feeding of the young) are simultaneously followed over short time intervals for a nesting season. Spatial distribution of the contaminants in prey resources is used on a cell by cell basis and their effects on certain behavior characteristics of adult birds (e.g. foraging efficiency, effects on flying efficiency, parental care) are taken into account. Results showed that sublethal effects could have a considerable effect on colony success. Appropriate selection of endpoints for risk assessment yields a variety of scenarios for colony success.  相似文献   
319.
杀虫双对土壤脲酶影响的研究   总被引:1,自引:0,他引:1  
通过对土壤脲酶受杀虫双影响的研究.结果表明,杀虫双对不同生态区土壤脲酶活性具有明显的抑制作用,随杀虫双浓度的增加,酶活性持续减小、计算得到了土壤酶活性的生态剂量ED50值,获得了北方(?)土和南方红壤污染的;临界浓度为489和246g/kg;Langmuir模型可较好表征酶活性与尿素浓度间的定量关系;土壤脲酶活性和最大表观酶活性均可表征土壤受杀虫双污染程度的大小。  相似文献   
320.
Polder lakes in Flanders are stagnant waters that were flooded by the sea in the past. Several of these systems are colonized by exotic species, but have hardly been studied until present. The aim of the present study was: (1) to assess the influence of exotic macrobenthic species on the outcome of the Multimetric Macroinvertebrate Index Flanders (MMIF) and (2) to use classification trees for evaluating to what extent physical-chemical characteristics affect the presence of exotic species.In total, 27 mollusc and 10 macro-crustacean species were present in the monitored lakes of which respectively five and four were exotic. The exclusion of the exotic species from the MMIF resulted in a significant decline of this ecological index (−0.03 ± 0.04; p = 0.00). This elimination often resulted into a lower ecological water quality class and more samples were classified into the bad and poor ecological water quality classes.Single-target classification trees for Gammarus tigrinus and Potamopyrgus antipodarum were constructed, relating environmental parameters and ecological status (MMIF) to the occurrence of both exotic invasive species. The major advantages of using single-target classification trees are the transparency of the rule sets and the possibility to use relatively small datasets. However, this classification technique only predicts a single-target attribute and the trees of the different species are often hard to integrate and use for water managers. As a solution, a multi-target approach was used in the present study. Exotic molluscs and crustaceans communities were modelled based on environmental parameters and the ecological status (MMIF) using multi-target classification trees. Multi-target classification trees can be used in management planning and investment decisions as they can lead to integrated decisions for the whole set of exotic species and avoid the construction of many models for each individual species. These trees provide general insights concerning the occurrence patterns of individual crustaceans and molluscs in an integrated way.  相似文献   
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